Nearest Stars

Of especial interest are the few stars that we know are the nearest to us, and the following table includes all those whose parallax is 0".20 or greater. There are nineteen in all and nearly half of them are binary systems. The radial motions given are relative to the sun. The transverse velocities are formed by using the measured parallaxes to transform proper motions into linear measures. They are given by Eddington in his "Stellar Movements"

These stars are distant less than five parsecs (about 16 light-years) from the sun, so they make up the closest fringe of the stellar universe immediately surrounding our system. The large number of binary systems is quite remarkable. Why some stars are single and others double is not yet known. By the spectroscopic method the proportion is not so large; Campbell finding that about one quarter of 1,600 stars examined are spectroscopic binaries, and Frost two-fifths to a half. The exceptional number of large velocities is very remarkable; the average transverse motion of the nineteen stars is fifty kilometers per second, whereas thirty is about what would have been expected.

As to star streams to which these nearest stars belong, eleven are in Stream I and eight in Stream II, in close accord with the ratio 3:2 given by the 6,000 stars of Boss's catalogue. "We are not able," says Eddington, "to detect any significant difference between the luminosities, spectra, or speeds of the stars constituting the two streams. The thorough interpenetration of the two star streams is well illustrated, since we find even in this small volume of space that members of both streams are mingled together in just about the average proportion."

Star's Name Magnitude Parallax in Seconds of Arc Proper Motion in Seconds of Arc Linear Velocity Km. per sec. Radial Velocity Km. per sec. Spectral Type Luminosity (Sun=1) Star Stream
Groombridge 34 8.2 0.28 2.85 48 Ma 0.010 I
Eta Cassiop 3.6 0.20 1.25 30 +10 F8 1.4 I
Tau Ceti 3.6 0.33 1.93 28 -16 K 0.50 II
Epsilon Erid 3.3 0.31 1.00 15 +16 K 0.79 II
CZ 5h 243 8.3 0.32 8.70 129 +242 G-K 0.007 II
Sirius -1.6 0.38 1.32 16 -7 A 48.0 II
Procyon 0.5 0.32 1.25 19 -3 F5 9.7 I ?
Lal. 21185 7.6 0.40 4.77 57 Ma 0.009 II
Lal. 21258 8.9 0.20 4.46 106 Ma 0.011 I
OA (N) 11677 9.2 0.20 3.03 72 0.008 I
Alpha Centauri 0.3 0.76 3.66 23 -22 G,K5 {
{ 2.0 0.6
{ 2.0

Solar System Links

Sabalico Logo
Sabalytics Logo
Senty Logo
SEO Guide Logo
World Map Logo
rStatistics Logo
Day Map Logo
Time Zone Logo
Galaxy View Logo
Periodic Table Logo
My Location Logo
Weather Track Logo
Sprite Sheet Logo
Barcode Generator Logo
Test Speed Logo
Website Tools Logo
Image Tools Logo
Color Tools Logo
Text Tools Logo
Finance Tools Logo
File Tools Logo
Data Tools Logo
History of Humanity - History Archive Logo
History of Humanity - History Mysteries Logo
History of Humanity - Ancient Mesopotamia Logo
History of Humanity - Persian Empire Logo
History of Humanity - Alexander the Great Logo
History of Humanity - Roman History Logo
History of Humanity - Punic Wars Logo
History of Humanity - Golden Age of Piracy Logo
History of Humanity - Revolutionary War Logo